Guard Valkyrie fire arc for heavy bolter sponsons

What is the fire arc of the sponson heavy bolters? Is it just the sides, is it 180 degrees, thus forward firing? The model looks like the bolters could conceivably fire forward, but what is the answer....

No mention of the fire arc in the Guard codex.

Not in the main rule book

Not in the FAQ

Weapons generally have whatever fire arc they are physically capable of, or if hull-mounts, and the model can move 180degrees

_________________Though our tanks and artillery are mighty, it is the vast ranks of Imperial Guardsmen that shall trample the enemy to dust - let them come.

You have to be very careful with firing arcs, and you determine it by how it is supposed to move along the model. Obviously if it's glued that won't penalise you. An example is the necron ghost barge which has 5 guns along each side. Now those guns are built to be able to only move up and down and not left to right, so the barge has to point its guns to the target that it wants to shoot at. Just like a space marine vindicator would as well for another example.

Anarkhia wrote: An example is the necron ghost barge which has 5 guns along each side. Now those guns are built to be able to only move up and down and not left to right, so the barge has to point its guns to the target that it wants to shoot at. Just like a space marine vindicator would as well for another example.

Not exactly. According to necrons FAQ:

Q: What is the arc of fire for a gauss flayer array? (p53)A: As it is mounted on the hull it will have a 45 degree arc offire. However it is slightly unusual in that it has multiple gunbarrels. As long as you can draw line of sight along one ofthem, you can target the unit

And as far as I remember everything mounted on hull has 45 degree arc, while turret/sponson arc is the "real" one. Am I right?